Historically, generators, which can easily weigh up to 850 tons supported by up to 20-30 feet have been aligned with their counterparts vertically through the use of jacks and shims and horizontally through the use of large steel beams, which lay under the generator across the concrete foundation, having uprights welded to each end. These vertical beams allow the placement of a jack to exert a horizontal push while sliding the entire weight of the machine on the 20-30 feet. Pushing a 38′×15′850 ton box while sliding against the resistance of the 20-30 feet tends to place bending stress on the device. Further, it is difficult to stop the move at 0.002 inches once you have established enough hydraulic pressure to overcome the friction of the system. A perfectly aligned machine sits level of even distribution with weight across all of its feet. A lack of even distribution results in torqued machine leading to a wide variety of premature problems. A perfectly aligned machine is also perfect at the coupling and some of the installations have a requirement of less than 0.001 inch per vertical and horizontal offset across the coupling. This requires placing a 250 to 850 ton machine in a spot with tolerances less than ⅓ the thickness of a human hair.
One known prior art attempt at solving this problem is found in U.S. Pat. No. 5,090,664, in the name of McCullough et al, dated Feb. 25, 1992, which discloses a combination jack and roller for movement of heavy loads. The structure relies on opposing wedges for vertical movement and a plurality of roller bearings for limited horizontal movement